From 0d6526f82c3cdefcca47f73f5fc08dc6f335eac6 Mon Sep 17 00:00:00 2001 From: Tim Chen Date: Mon, 21 Sep 2026 17:37:22 -0700 Subject: sched/cache: Keep nr_pref_llc_running in the runnable domain, to fix LLC mis-scheduling bug alb_break_llc() decides whether to break LLC preference during active load balance. It does so by testing that every runnable fair task on the source rq prefers its LLC: env->src_rq->nr_pref_llc_running == env->src_rq->cfs.h_nr_runnable But the two counters cover different sets. nr_pref_llc_running is updated in account_llc_enqueue()/account_llc_dequeue(), next to cfs_rq->nr_queued, so it follows queued tasks. h_nr_runnable is updated in set_delayed()/ clear_delayed() and drops delay-dequeued tasks. So under DELAY_DEQUEUE, a preferring task that goes to sleep stays counted in nr_pref_llc_running while h_nr_runnable falls. The equality then breaks, alb_break_llc() returns false, and active balance is free to pull a task off its preferred LLC. Active balance only moves runnable tasks, and this is the only LLC check it consults: once the stopper runs, LBF_ACTIVE_LB skips the per-task test in can_migrate_task(). The runnable set is the one we want. Fix it on the counter side. A task should be counted in nr_pref_llc_running exactly while it is both queued on its preferred LLC (pref_llc_queued) and runnable (!sched_delayed). Define that membership once in task_pref_llc_runnable(), and adjust the counter only through pref_llc_running_inc()/pref_llc_running_dec() from the four sites that change either input: account_llc_enqueue(), account_llc_dequeue(), set_delayed() and clear_delayed(). Gating every update on the same predicate keeps the delay, wake and dequeue paths from double-counting or underflowing; see the comments at those sites for the ordering. nr_llc_running and sd->llc_counts are not touched and stay on queued semantics. Fixes: 714059f79ff0 ("sched/cache: Handle moving single tasks to/from their preferred LLC") Closes: https://lore.kernel.org/lkml/20260827135000.735138-1-zhanxusheng@xiaomi.com/ Reported-by: Zhan Xusheng Suggested-by: Chen Yu Signed-off-by: Tim Chen Signed-off-by: Peter Zijlstra (Intel) Signed-off-by: Ingo Molnar Reviewed-by: Kayra Cizmeci Cc: # v7.2.x Link: https://patch.msgid.link/06af61afedac32e6477f57feb4d658f6c411c3af.1790035273.git.tim.c.chen@linux.intel.com --- drivers/hid/hid-glorious.c | 98 ++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 98 insertions(+) create mode 100644 drivers/hid/hid-glorious.c (limited to 'drivers/hid/hid-glorious.c') diff --git a/drivers/hid/hid-glorious.c b/drivers/hid/hid-glorious.c new file mode 100644 index 000000000..5bbd81248 --- /dev/null +++ b/drivers/hid/hid-glorious.c @@ -0,0 +1,98 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/* + * USB HID driver for Glorious PC Gaming Race + * Glorious Model O, O- and D mice. + * + * Copyright (c) 2020 Samuel Čavoj + */ + +/* + */ + +#include +#include + +#include "hid-ids.h" + +MODULE_AUTHOR("Samuel Čavoj "); +MODULE_DESCRIPTION("HID driver for Glorious PC Gaming Race mice"); + +/* + * Glorious Model O and O- specify the const flag in the consumer input + * report descriptor, which leads to inputs being ignored. Fix this + * by patching the descriptor. + * + * Glorious Model I incorrectly specifes the Usage Minimum for its + * keyboard HID report, causing keycodes to be misinterpreted. + * Fix this by setting Usage Minimum to 0 in that report. + */ +static const __u8 *glorious_report_fixup(struct hid_device *hdev, __u8 *rdesc, + unsigned int *rsize) +{ + if (*rsize == 213 && + rdesc[84] == 129 && rdesc[112] == 129 && rdesc[140] == 129 && + rdesc[85] == 3 && rdesc[113] == 3 && rdesc[141] == 3) { + hid_info(hdev, "patching Glorious Model O consumer control report descriptor\n"); + rdesc[85] = rdesc[113] = rdesc[141] = \ + HID_MAIN_ITEM_VARIABLE | HID_MAIN_ITEM_RELATIVE; + } + if (*rsize == 156 && rdesc[41] == 1) { + hid_info(hdev, "patching Glorious Model I keyboard report descriptor\n"); + rdesc[41] = 0; + } + return rdesc; +} + +static void glorious_update_name(struct hid_device *hdev) +{ + const char *model = "Device"; + + switch (hdev->product) { + case USB_DEVICE_ID_GLORIOUS_MODEL_O: + model = "Model O"; break; + case USB_DEVICE_ID_GLORIOUS_MODEL_D: + model = "Model D"; break; + case USB_DEVICE_ID_GLORIOUS_MODEL_I: + model = "Model I"; break; + } + + snprintf(hdev->name, sizeof(hdev->name), "%s %s", "Glorious", model); +} + +static int glorious_probe(struct hid_device *hdev, + const struct hid_device_id *id) +{ + int ret; + + hdev->quirks |= HID_QUIRK_INPUT_PER_APP; + + ret = hid_parse(hdev); + if (ret) + return ret; + + glorious_update_name(hdev); + + return hid_hw_start(hdev, HID_CONNECT_DEFAULT); +} + +static const struct hid_device_id glorious_devices[] = { + { HID_USB_DEVICE(USB_VENDOR_ID_SINOWEALTH, + USB_DEVICE_ID_GLORIOUS_MODEL_O) }, + { HID_USB_DEVICE(USB_VENDOR_ID_SINOWEALTH, + USB_DEVICE_ID_GLORIOUS_MODEL_D) }, + { HID_USB_DEVICE(USB_VENDOR_ID_LAVIEW, + USB_DEVICE_ID_GLORIOUS_MODEL_I) }, + { } +}; +MODULE_DEVICE_TABLE(hid, glorious_devices); + +static struct hid_driver glorious_driver = { + .name = "glorious", + .id_table = glorious_devices, + .probe = glorious_probe, + .report_fixup = glorious_report_fixup +}; + +module_hid_driver(glorious_driver); + +MODULE_LICENSE("GPL"); -- cgit v1.3.1